Device for hybrid plasma processing

ABSTRACT

A device for hybrid plasma processing, particularly for deposition of thin films and for plasma treatment of samples, in a plasma reactor with pumping system characterized in that at least one feeder of microwave power ( 2 ) is installed in the plasma reactor ( 1 ) and connected to a microwave generator ( 3 ) for generation of a microwave plasma ( 4 ) in contact with at least one hollow cathode ( 5 ) in the plasma reactor, where the hollow cathode is powered from a cathode power generator ( 6 ). At least one inlet for a processing gas ( 7 ) is installed behind the hollow cathode and the gas is admitted into the plasma reactor through the hollow cathode where a hollow cathode plasma ( 9 ) is generated. A magnetic element ( 10 ) is used for generation of a perpendicular magnetic field ( 11 ) and/or a longitudinal magnetic field ( 12 ) at an outlet ( 13 ) from the hollow cathode.

TECHNICAL FIELD

The present invention relates to a device for hybrid plasma processingand, more particularly, for deposition of thin films and plasmatreatment of surfaces of samples using a hybrid microwave and hollowcathode plasma.

BACKGROUND OF THE INVENTION

The plasma processes in microwave discharges are based on electrons,because heavy ions are not able to follow changes of the microwavefield. The microwave plasma might be produced by: (i) anisotropicgeneration, and (ii) an anisotropic generation in a magnetic field. Theisotropic generation represents simple absorption of the microwaveenergy in the plasma without any preferential directions defined byexternal forces. The isotropic plasma has an upper electron densitylimit, so called cutoff density, which depends linearly on the square ofthe generator frequency. The most common anisotropic generation is theElectron Cyclotron Resonance (ECR). There the microwave power isabsorbed in the plasma in a magnetic field having inductionB=B_(ce)=2πm/e, where f is the frequency of the generator (typically2.4·10⁹ s⁻¹), m and e are the electron mass (9.1·10⁻³¹ kg) and electroncharge (1.6·10⁹ As), respectively. The value of the ECR field fortypical microwave generators is B_(ce)=8.57·10⁻² Tesla. In theanisotropic microwave plasmas the plasma electron density may evenexceed the cutoff density. The plasma density in the microwave plasma istypically high (≧1010 cm⁻³), particularly in low pressure ECR plasmas,but the energy of ions is often insufficient. Contrary to this, in adirect current (DC) generation, or at lower frequencies, for example atradio frequency (RF) generation (order of 10⁶-10⁷ Hz) applied through anarbitrary RF electrode, the ions may follow the generating field andgain a sufficient energy. However, a high generation frequency in themicrowave case (order of 109 Hz) can provide higher plasma density thanany lower frequency generation at the same power, because of highercutoff density allowed. Therefore an additional DC or RF bias applied tosample holders or auxiliary electrodes is often necessary to increaseion energy in the microwave systems. The efficiency of the microwavegeneration is very sensitive to the geometry of the launching system.The conventional electrode less generation of the microwave plasmadoesn't need metal electrodes that may cause metal contamination. Butsuch systems often require additional electrodes for ion energy control,anyway. Moreover, because of a possibility of coating dielectric windowsat microwave inlets by absorbing films, the windows require specialarrangement with protecting film depositions in a technology using PECVD (Plasma Enhanced Chemical Vapor Deposition).

The microwave devices of different constructions have been used fordifferent surface treatments (see for instance M. Moisan and J.Pelletier, eds.: “Microwave Excited Plasmas”, Elsevier, Amsterdam,1992). During last decade the microwave plasma is frequently used fordeposition of carbonaceous films, like diamond or carbon nitrides. InU.S. Pat. No. 4,898,118 the generation of the microwave plasma isfulfilled in a reaction vessel disposed to penetrate through therectangular wave-guide. In U.S. Pat. No. 4,940,015 the reactor fordiamond film synthesis is based on a tunable evacuated microwave cavityadjacent to the rectangular wave-guide. The coupling of the microwavepower is fulfilled by an antenna inside the wave-guide and outside thelow pressure region directing the microwave power into the cavitythrough the dielectric window positioned in a bottom side of aparticularly designed cylindrical part of the cavity. In U.S. Pat. No.4,958,590 the generation of the microwave plasma is fulfilled inside areaction tube of particular design located inside a wave-guide ofspecified length. The plasma is generated in a travelling wave mode. Adevice with ECR microwave plasma is claimed in U.S. Pat. No. 4,915,979.In this patent the dimensions of reaction chamber are optimized withrespect to Larmor radii of electrons, so that the spatial uniformity ofthe plasma electron density can be improved. In a Swedish PatentApplication 9302222-6 a unique system was described for the isotropicmicrowave plasma generation. The system is based on a plasma slabgenerated by surface waves and used as an antenna for a subsequentgeneration of a bulk microwave plasma in resonator. An additionalelectrode in this system allows control of both the current to thesubstrate and coupling of the plasma antenna with the resonator (seee.g., Bárdos et al, J. Vac. Sci. Technol., 1995). A simple electrodegeneration of the microwave plasma has been recently reported for PE CVDof C—N films (Bardos et al, Proc. SVC Tech. Con. 1999). The systemcombines efficient low power generation with a possibility ofrestriction of the plasma zone at the processed surface and easyapplication of auxiliary fields. In the described present art theelectrodes in the microwave plasma were used only either as microwavelaunching antennas or as auxiliary applicators for additional electricfields. Additional fields in microwave plasma may be used for generationof independent plasma or plasma dependent on pre-ionization from theoriginal microwave plasma. These combinations may lead to more suitableadvanced processing plasma, denoted usually as a “dual plasma” or“hybrid plasma”. Example of a hybrid plasma generated in an anisotropic(magnetized) microwave plasma combined with DC and AC fields applied bya set of electrodes is claimed in Japanese patent No. 01191779 A by F.Kanji (1988). A typical example of dual plasma generated in an isotropicmicrowave plasma is claimed in U.S. Pat. No. 4,691,662 by T. A. Roppelet al. (1986). Here a disk microwave plasma acts as a source of excitedion and free radical species and electrons for the second plasma whichis hybrid in that it contains species from both microwave and DC (or RFdepending bias) excitation through metal plate means. The system maywork also with an anisotropic plasma in the ECR mode.

Contrary to “soft” microwave plasmas for chemistry-based treatments, forinstance plasma etching or PE CVD, the Physical Vapor Deposition (PVD)of films requires presence of a solid target (usually cathode) andeither high ion energies (for sputtering) or large electron (or ion)current for heating (evaporation) of the target. Very efficient“electrode-based” discharges for surface treatment are generated byhollow cathodes. The cathode is connected to a negative pole of a DCgenerator and the positive pole is connected to a suitable counteranode. Depending on the DC power the hollow cathode discharge can beexcited in a glow regime or in an arc regime. The principle of thehollow cathode discharge is based on its suitable geometry, where anelectron emitted from one cathode wall interacts with an equivalentelectric field with opposite orientation at the opposite wall. Thus theelectrons may oscillate between inner walls of the hollow cathode andsubstantially enhance the ionization of the present gas, or metaldeliberated from the cathode wall. Since 1983 the hollow cathode glowdischarges have been generated also by alternating currents (AC).Typical frequency of AC generators for this purpose is between 10⁵ s⁻¹and 10⁸ s⁻¹. The anode in the RF generated hollow cathodes is the RFplasma itself (a virtual anode), in contact with the real counterelectrode connected to the RF generator (Bardos et al., J. Non Cryst.Solids 97/98, 281 (1987)). Effects of additional magnetic fields havebeen found in hollow cathodes, see e.g. review by K. H. Schoenbach,invited paper at ICPIG 21, Bochum 1993, Proc. III, pp. 287-296. Afocused magnetic field was used in an apparatus for generation of alinear arc discharge for plasma processing (LAD) by Bardos et al. in aSwedish Patent Application 9403988-0 (U.S. Pat. No. 5,908,602). In thisapparatus a pair of electrode plates placed opposite to each other formsparallel-plate hollow cathode, negative with respect to the surroundingplasma. The magnetic field perpendicular to the cathode plates andlocated close to the cathode outlet facilitates the hollow cathodedischarge between the plates in the outlet slit. The hot zones areformed at both plates along the outlet slit due to an enhanced ionbombardment of the plate surfaces. The magnetic field geometry in theLAD system is stationary in both time and space. In the Swedish PatentApplication 9704260-0 by Barankova et al. a plasma processing apparatuswith rotary magnets for obtaining an adjustable time variable magneticfield has been claimed. The rotary permanent magnet systems, comprisingindividual permanent magnets with maximum magnetic induction more than10⁻¹ Tesla, may be installed along the outlet slit of the linear hollowcathode for better control of the hollow cathode discharge.

Because of high production of electrons even in glow regimes the hollowcathodes have been used since 1971 as both an electron source and theworking gas ionization source in plasma processing devices for plasmaassisted evaporation. The hollow cathode may enhance sputtering rate ofmagnetrons when used as an auxiliary source of electrons close to thetarget erosion zone (U.S. Pat. No. 4,588,490 1986 by J. J. Cuomo etal.). An another suitable application of the hollow cathode is itscombination with an arc evaporator (see A. Lunk, Vacuum, 1990). Theseapplications might be considered as an example of hollow cathodeassisted hybrid plasma. However, no devices utilizing both the hollowcathode discharge and the microwave plasma simultaneously in a suitablehybrid system have been described yet. There are also no works orresults yet reporting about combinations of the magnetized hollowcathodes with other plasma systems.

SUMMARY OF THE INVENTION

An object of the present invention is therefore to overcome the abovedescribed prior art discoveries and drawbacks and to provide an improveddevice for hybrid plasma processing, particularly for deposition of thinfilms and plasma treatment of surfaces of samples.

A device according to the present invention is set forth by theindependent claim 1 and different embodiments of the invention are setforth by the dependent claims 2 to 9.

BRIEF DESCRIPTION OF THE DRAWINGS

The objects, features and advantages of the present invention as mentioned above may best be understood by making reference to the followingdescription taken together with the accompanying drawings, wherein samereference numerals are used throughout the description indicating sameor corresponding elements, and in which:

FIG. 1 is a schematic plan view of the device for hybrid plasmaprocessing, particularly for deposition of thin films or plasmatreatment of surfaces of samples in a hybrid microwave and hollowcathode plasma in a first embodiment according to the present invention;

FIG. 2 is a schematic plan view of an EXAMPLE 1 of the device for hybridplasma processing in a second embodiment of the present invention, inwhich a microwave antenna is installed into the plasma reactor through adielectric window as a part of the hollow cathode;

FIG. 3 is a schematic plan view of an EXAMPLE 2 of the device for hybridplasma processing in a third embodiment of the present invention, inwhich the plasma reactor equipped by a tuning element forms a microwaveresonant cavity with respect to the frequency of the microwave generatorand the magnetic induction of the magnetic means is variable in timeand/or in space;

FIG. 4 is a schematic plan view of an EXAMPLE 3 of the device for hybridplasma processing in a fourth embodiment of the present invention, inwhich the plasma reactor is opened to an ambient gas and its outlet hasform of coaxial wave-guide with central conductor represented by thehollow cathode;

FIG. 5 is a schematic plan view of an EXAMPLE 4 of the device for hybridplasma processing in a fifth embodiment of the present invention, inwhich the plasma reactor has an outlet opened to an ambient gas and theoutlet has a form of tapered wave-guide in which a hollow cathode isinstalled; and

FIG. 6 is a schematic plan view of an EXAMPLE 5 of the device for hybridplasma processing in a sixth embodiment of the present invention, inwhich the plasma reactor is electrically insulated from the feedingwave-guide and its outlet has form of a tapered rectangular wave-guiderepresenting double hollow cathode.

DETAILED DESCRIPTION

Referring to FIG. 1 of the drawings, the first embodiment of the devicefor hybrid plasma processing according to the present invention will bedescribed. At least one feeder of the microwave power 2 connected to amicrowave generator 3 is installed in the plasma reactor 1 to generate amicrowave plasma 4 in contact with at least one hollow cathode 5 in thisplasma reactor. The hollow cathode is powered from a cathode powergenerator 6 and comprises at least one inlet for a processing gas 7,installed behind the hollow cathode. The cathode power generator may beeither DC or AC. The processing gas is admitted into the plasma reactorthrough the hollow cathode, where the hollow cathode plasma 9 isgenerated. The plasma reactor is equipped by a pumping system 8 forpumping gases from the plasma reactor and keeping the gas pressure atdesired value in case of sub-atmospheric operation of the system. Incase of atmospheric pressure operation of the device the pumping systemhas an auxiliary function e.g., for pumping of residual gases afterindividual operating cycles. A magnetic means 10 is provided forgeneration of a perpendicular magnetic field 11 and/or a longitudinalmagnetic field 12 with respect to the axis of the hollow cathode at itsoutlet 13. The magnetic field may have several effects, depending onboth its geometry and its induction. It may act as a simple magneticconfinement of the plasma around the outlet 13 of the hollow cathode. Itmay also enable a resonant absorption of the microwave power andgeneration of the ECR microwave plasma, if the field induction isB≧B_(ce). And, moreover the magnetic field may be used for enhancementof the hollow cathode effect in the outlet of the hollow cathode andgeneration of the hollow cathode plasma. Simultaneous generation of themicrowave plasma and the hollow cathode plasma helps in pre-ionizationand sustenance of both individual plasmas and forms hybrid plasma 14.This hybrid plasma consisting of the microwave plasma 4 and the hollowcathode plasma 9 is used for processing of samples 15 placed on a sampleholder 16 in contact with this hybrid plasma. A further inlet ofadditional processing gas 17 is installed in the plasma reactor outsidethe hollow cathode. A counter electrode 18 connected to the cathodepower generator serves as an auxiliary anode in the hollow cathodeplasma circuit. The counter electrode may be represented by conductivewalls of the plasma reactor and/or by the sample holder with samples.

EXAMPLES

Five examples of embodiments the microwave apparatus for plasmaprocessing according to the present invention are described below:

Example 1 of FIG. 2 describes an embodiment of the device for hybridplasma processing referred in FIG. 1, wherein feeding of the microwavepower into the plasma reactor is accomplished by a microwave antenna 19coupled to a feeding wave-guide 21 and installed in the plasma reactorthrough a dielectric window 20. The microwave antenna represents part ofthe hollow cathode coupled to the cathode power generator 6. The antennamay also serve as an inlet of the processing gas 7. The hollow cathodemay be of deliberate shape, for instance a simple tube continuation ofthe antenna, or parallel plates installed at the antenna in the reactor.An advantage of this arrangement is for instance possibility to move theantenna—hollow cathode in the reactor, or possibility to apply anadditional bias to the hollow cathode, superimposed to the cathode powergenerator.

Example 2 of FIG. 3 describes an embodiment of the device for hybridplasma processing, wherein the plasma reactor 1 is equipped by a tuningelement 22 and forms a microwave resonant cavity with respect to thefrequency of the microwave generator. Advantage of this arrangement ispossibility to enhance absorption of the microwave power and generationof the microwave plasma in the reactor where the hollow cathode isinstalled. Another option of the device according to the presentinvention and shown in this example is possibility to arrange themagnetic induction of the magnetic means 10 variable in time and/or inspace. This may be arranged by spinning or vibrating magnets, byelectromagnetic coils powered by an AC generator, etc.

Example 3 of FIG. 4 describes an embodiment of the device for hybridplasma processing, wherein the plasma reactor 1 has at least one outletopened to an ambient gas and this outlet has form of a coaxialwave-guide 23 with a central conductor represented by the hollow cathode5. For high pressure regimes the hollow cathode should have a smalldistance between the opposite inner walls, typically less than 1 mm. Thehybrid plasma 14 is generated in contact with the samples 15. In casesof atmospheric or higher pressures during operation of the device theambient gas, for instance air, might have an undesirable effect eitheron the hybrid plasma or on the processing regimes at the samples. Forthis reason the device may be equipped with a shielding 24 for reducinginteraction of the hybrid plasma with an ambient gas.

Example 4 of FIG. 5 describes an embodiment of the device for hybridplasma processing, wherein the plasma reactor 1 has at least one outletopened to an ambient gas. This outlet has form of a tapered wave-guide25 in which at least one hollow cathode 5 is installed. In thisembodiment of the device the hollow cathode is installed withoutelectrical contact with the wave-guide 1 and the wave-guide serves as acounter electrode for the hollow cathode. In a simple case ofrectangular tapered wave-guide and a linear hollow cathode the magneticmeans may be accomplished for instance by opposite permanent magnets orelectromagnetic coils. The outlet of the reactor 1 may have circular orelliptic form and the suitable form of the hollow cathode may becircular or elliptic, but also rectangular or composed from an array ofmultiple hollow cathodes.

Example 5 of FIG. 6 describes an embodiment of the device for hybridplasma processing, wherein the plasma reactor 1 is electricallyinsulated from the feeding wave-guide 21 by an insulator 26. The plasmareactor has at least one outlet opened to an ambient gas and this outlethas form of the tapered rectangular wave-guide, in which at least onehollow cathode is integrated in a way that the tapered wave-guide is apart of at least one hollow cathode 5. In this case the plasma reactorhas a double function. It represents a wave-guide with a tapered outletand a hollow cathode or system of hollow cathodes, for instance amulti-slit cathode, integrated in this outlet. The reactor is connectedto the cathode power generator for excitation of the hollow cathodeplasma and the microwave power delivered into the reactor may excite themicrowave plasma behind or inside the hollow cathode part. The reactoris provided by inlet of the processing gas 7, which might be combinedwith an inlet of the additional processing gas 17, or the inlet of theadditional processing gas is positioned at the outlet of the reactor.

The device for hybrid plasma processing according to the presentinvention has an advantage particularly in applications, where eithervery low or very high gas pressure (including atmospheric and higherpressure) regimes are desirable with controllable parameters at highplasma density. In both cases the microwave plasma might be main sourceof pre-ionization for the hollow cathode. Very low pressure regimes(below 1 mTorr) may be favorably performed in magnetic fields ofinduction B≧B_(ce).

The device for hybrid plasma processing according to the invention canbe utilized not only for the deposition of films, but also for otherkinds of plasma processing, e.g. dry etching, plasma cleaning,oxidizing, plasma nitridization, etc.

The combination of the microwave plasma with the hollow cathode plasmaaccording to the invention enables an independent control of theelectron based microwave dissociation and radical activation of theactive gas with an ionization and ion energy control through the hollowcathode. This also brings about a unique possibility to combine thehollow cathode PVD in an arc regime with the microwave plasma CVD fordeposition of composite films.

A device for hybrid plasma processing according to this invention hasbeen described with reference to its preferred embodiments. It istherefore to be understood that numerous changes and variations will bepossible thereof without departing from the spirit and scope of theinvention as defined by the attached claims.

1. A device for hybrid plasma processing comprising: a plasma reactor;at least one hollow cathode in the plasma reactor and a hollow cathodepower generator, the hollow cathode having an outlet; a microwave plasmagenerator installed in the plasma reactor, the microwave plasmagenerator comprising at least one microwave power feeder and a microwavegenerator connected to the microwave power feeder; at least one firstprocessing gas inlet into the at least one hollow cathode; a magneticfield generator constructed and arranged so as to be able to generate amagnetic field at the outlet of the hollow cathode in the plasmareactor, the magnetic field having an orientation that is at least oneof perpendicular and longitudinal with reference to a longitudinal axisof the hollow cathode; a second processing gas inlet having an outletinside the reactor and outside the hollow cathode; and a counterelectrode connected to the hollow cathode power generator; wherein thehollow cathode is specifically constructed and arranged to have ageometry such that, when powered by the hollow cathode power generatorto produce a hollow cathode plasma, the hollow cathode demonstrates thehollow cathode effect, in which an electron emitted from one wall of thehollow cathode interacts with an equivalent electric field with oppositeorientation at an opposite wall; and wherein the microwave power feederand the hollow cathode are positioned with respect to one another suchthat when the microwave power feeder generates a microwave plasma, themicrowave plasma is in contact with the outlet of the at least onehollow cathode, and wherein the microwave plasma and the hollow cathodeplasma combine to produce a hybrid plasma.
 2. The device of claim 1,wherein the plasma reactor comprises a conductive wall, and wherein theconductive wall is connected to the hollow cathode power generator asthe counter electrode.
 3. The device according to claim 2, wherein themicrowave power feeder comprises a microwave antenna coupled to amicrowave wave-guide, the microwave antenna being installed in theplasma reactor through a dielectric window, the microwave antenna beingconstructed as the at least one processing gas inlet to the hollowcathode, the microwave antenna being arranged so as to connect thehollow cathode with the hollow cathode power generator.
 4. The deviceaccording to 1, wherein the plasma reactor comprises a support for anobject to be positioned within the hybrid plasma and wherein the supportis connected to the hollow cathode power generator as the counterelectrode.
 5. The device according to claim 1, wherein the microwavepower feeder comprises a microwave antenna coupled to a microwavewave-guide, the microwave antenna being installed in the plasma reactorthrough a dielectric window, the microwave antenna being constructed asa part of the hollow cathode so as to serve as the at least one firstprocessing gas inlet to the hollow cathode, the microwave antenna beingarranged so as to connect the hollow cathode with the hollow cathodepower generator.
 6. The device according to claim 5, wherein magneticinduction of the magnetic field generator is variable in at least one oftime and space.
 7. The device according to claims 6, wherein themicrowave power feeder comprises at least one outlet opened to anambient gas in the form of a coaxial microwave wave-guide having as acentral conductor the hollow cathode; and wherein the plasma reactorfurther comprises: a support for an object to be positioned within thehybrid plasma, wherein the support is connected to the hollow cathodepower generator as the counter electrode; and a shielding arrangedbetween the support and the outlet of the hollow cathode.
 8. The deviceaccording to claims 6, wherein the microwave power feeder comprises atleast one outlet opened to an ambient gas in the form of a taperedwave-guide in which the at least one hollow cathode is installed.
 9. Thedevice according to claim 5, wherein the microwave power feedercomprises at least one outlet opened to an ambient gas in the form of acoaxial microwave wave-guide having as a central conductor the hollowcathode; and wherein the plasma reactor further comprises: a support foran object to be positioned within the hybrid plasma, wherein the supportis connected to the hollow cathode power generator as the counterelectrode; and a shielding arranged between the support and the outletof the hollow cathode.
 10. The device according to claim 5, wherein themicrowave power feeder comprises at least one outlet opened to anambient gas in the form of a tapered wave-guide in which said at leastone hollow cathode is installed.
 11. The device according to claim 10,wherein the hollow cathode is electrically insulated from the microwavepower feeding wave-guide by an insulator, the outlet having a form of atapered rectangular wave-guide in which said at least one hollow cathodeis disposed, said tapered wave-guide being connected to the hollowcathode power generator as the counter electrode.
 12. The deviceaccording to claim 10, wherein the hollow cathode is electricallyinsulated from the microwave power feeding wave-guide by an insulator,the tapered wave-guide being connected to the hollow cathode powergenerator as the counter electrode.
 13. The device according to claim 5,wherein the plasma reactor is constructed as a microwave resonant cavitywith respect to a frequency of the microwave generator, the plasmareactor being equipped with a tuning element for tuning a resonantabsorption of power from the microwave generator.
 14. The deviceaccording to claim 1, wherein the plasma reactor is constructed andarranged so as to operate as a microwave resonant cavity with respect toa frequency of the microwave generator, the plasma reactor furthercomprising a tuning element constructed so as to allow tuning a resonantabsorption of power from the microwave generator.
 15. The deviceaccording to claim 14, wherein magnetic induction of the magnetic fieldat the outlet of the hollow cathode reaches at least electron cyclotronresonance value B_(ce) with respect to the frequency of the microwavegenerator.
 16. The device according to claim 1, wherein magneticinductance of the magnetic field at the outlet of the hollow cathodereaches at least electron cyclotron resonance value B_(ce) with respectto the frequency of the microwave generator.
 17. The device according toclaim 16, wherein magnetic induction of the magnetic field generator isvariable in at least one of time and in space.
 18. The device accordingto claims 16, wherein the microwave power feeder comprises at least oneoutlet opened to an ambient gas in the form of a coaxial microwavewave-guide having as a central conductor the hollow cathode; and whereinthe plasma reactor further comprises: a support for an object to bepositioned within the hybrid plasma, wherein the support is connected tothe hollow cathode power generator as the counter electrode; and ashielding arranged between the support and the outlet of the hollowcathode.
 19. The device according to claims 16, wherein the microwavepower feeder comprises at least one outlet opened to an ambient gas inthe form of a tapered wave-guide in which the at least one hollowcathode is installed.
 20. A device for hybrid plasma processing in aplasma reactor including a pumping system, the device comprising: aplasma reactor; means for generating a microwave plasma in the plasmareactor; means for generating a hollow cathode plasma in the plasmareactor, the means for generating the hollow cathode plasma comprisingopposing walls, wherein the hollow cathode plasma is one in which anelectron emitted from one of the opposing walls interacts with anequivalent electric field with opposite orientation at another of theopposing walls; means for introducing at least one first processing gasinto the means for generating a hollow cathode plasma; means forgenerating at least one of a perpendicular and a longitudinal magneticfield at the hollow cathode plasma; means for introducing a secondprocessing gas inside the reactor and outside the hollow cathodegenerating means; and a counter electrode connected to the hollowcathode generating means; wherein the microwave plasma generating meansand the hollow cathode generating means are positioned with respect toone another such that the microwave plasma and the hollow cathode plasmacombine to produce a hybrid plasma.
 21. A device for hybrid plasmaprocessing in a plasma reactor including a pumping system, the devicecomprising: a plasma reactor; a microwave generator and a microwavegenerator power source connected to the plasma reactor; means forgenerating a hollow cathode plasma in the plasma reactor, the means forgenerating the hollow cathode plasma comprising opposing walls, whereinthe hollow cathode plasma is one in which an electron emitted from oneof the opposing walls interacts with an equivalent electric field withopposite orientation at another of the opposing walls; at least onefirst processing gas inlet into the hollow cathode generating means; amagnetic field generator constructed and arranged so as to be able togenerate at least one of a perpendicular and a longitudinal magneticfield at the hollow cathode plasma generating means; a second processinggas inlet having an outlet inside the reactor and outside the hollowcathode; and a counter electrode connected to the hollow cathodegenerating means; wherein the microwave generator and the hollow cathodegenerating means are positioned with respect to one another such thatwhen the microwave generator is powered by the microwave generator powersource, the microwave generator produces a microwave plasma that is incontact with the hollow cathode plasma, and wherein the microwave plasmaand the hollow cathode plasma combine to produce a hybrid plasma.